In the IPC method, sleeves (garments) 301a and 301b, as illustrated in FIGS. 34 and 35 are wound around a lower limb or the bottom of the foot, and, blood flowing in a vein is extruded by using a pressure applied by a pressurizing pump (IPC pump), a vein blood flow rate is increased, and a fibrinolytic action is stimulated. In this IPC method, at the time of starting the operation, it is necessary to check whether connection tubes 4a1, 4a2, 4a3; 4b1, 4b2, and 4b3 are reliably connected, whether there is torsion or folding in the connection tubes 4a1, 4a2, 4a3; 4b1, 4b2, and 4b3, whether there is an air leakage from the connection tubes 4a1, 4a2, 4a3; 4b1, 4b2, and 4b3, whether there is an air leakage in the connector, whether there is an air leakage or a failure in a sleeve, a calf pump, or a foot pump, and the like.
In the earlier technology, an apparatus for monitoring the operation state of a high-pressure fluid-pressurizing pump as recited in patent literature (PTL) 1, another apparatus for inspecting only a defect of a tube alone as recited in PTL 2, and the like are known. However, in a system targeting a low-pressure regime of about 5 to 10 kPa used for medical instrument, a defect in the suppression pressure at the time of winding sleeves 301a and 301b or the like around a human body and the like are complex events accompanying a change of minute levels in the pressure. Accordingly, in the case of a fluid path of the low-pressure regime used for medical instrument, the detection of defects and the investigation into the causes of the defects require a minute determination, which will accompany empirical rules, and are very difficult to perform. Accordingly, when medical instrument having a system structure implemented by the fluid path of the low-pressure regime, which requires detection of change in minute levels in the pressure, is assigned as a device-under-test (DUT), it is difficult to discriminate the failures in the hardware or a system implementing the DUT such as a pressurizing pump, from the leakage or the defect in connection tubes 4a1, 4a2, 4a3; 4b1, 4b2, 4b3 or the like used in the DUT, or from the defect in the attachment of sleeves 301a and 301b used in the DUT, or from the defect in the suppression pressure, in a simplified manner. Therefore, in the earlier technology, there has been no proposal for a fluid-path tester or a fluid-path testing-method capable of discriminating the leakage of a dedicated tube from problems associated with the system including a compressor, in a simplified manner.